There is some debate on the subject, but the combination of black skin and clear fur is probably the best for keeping the polar bear warm while not giving away its position when hunting. The black color of the skin is the best for absorbing energy from the Sun—objects that appear black don’t reflect any wavelengths of light. The clear fur allows that light to get to the skin, but still looks white so the bear can blend in with the surrounding ice and snow.

A few years ago, or maybe you heard this recently because it has achieved urban legend status, a rumor you may have heard is that polar bear fur is actually like a fiber optic network for harnessing or focusing sunlight toward the bear’s skin. While this would have been cool, it’s unfortunately completely bogus.